Swine Influenza Hemagglutinin Variants - Patent 8088393

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Swine Influenza Hemagglutinin Variants - Patent 8088393 Powered By Docstoc
Description: REFERENCE TO THE SEQUENCE LISTING This application incorporates by reference a Sequence Listing submitted with this application as text file entitled seq list_FL265US_MED0459US created on Feb. 2, 2011 and having a size of 30 kilobytes.BACKGROUND OF THE INVENTION The global spread of swine-origin influenza A (H1N1) viruses in humans in April 2009 marked the first influenza pandemic in 41 years. Over 35,000 people were infected with this novel H1N1 virus as of Jun. 15, 2009. Last century, an H1N1influenza virus also caused the devastating 1918-19 pandemic. In addition, an H1N1 virus derived from swine caused an abortive pandemic in 1976. The 1918 influenza virus caused a mild outbreak in the spring of 1918 and a lethal wave globally in thefall of that year, killing as many as 50 million people worldwide. Although the 2009 swine-origin H1N1 influenza virus was viewed as mild in early 2009, the possibility exists that this virus may mutate and become more virulent by the fall of 2009. Therefore there is an urgent need to develop an effective vaccine to prevent a severe pandemic caused by the 2009 H1N1 viruses. 6:2 reassortant influenza viruses (having the HA and NA segments of swine-origin influenza A (H1N1) viruses and the "backbone" segments of attenuated influenza viruses) useful for vaccine development, both live and killed vaccine have beenisolated yet most strains isolated thus far display low titers in eggs. The same isolates infect MDCK cells poorly and form tiny plaques with poor CPE. Additionally, a severe loss of virus potency is observed after virus filtration. Accordingly, theinitially isolated H1N1 reassortant influenza virus strains are poor candidates for the development of a vaccine strain. The present invention provides new and/or newly isolated swine influenza H1 hemagglutinin variants that are capable of use for the production of numerous types of vaccines as well as in research, diagnostics, etc. The present invention furtherprovides metho